Madonna

If the secret Madonna has to tell on this live album (drawn from 2004's Re-Invention tour) is that she fakes that British accent, well, Madge, the jig is up. Her dialect-by-marriage (and a few other Madonna-isms, like when she raps about lattes) aside, what's not a secret is that Madonna's still the queen of the dancefloor. Her voice sounds bloody good (check her rage-rock scream on "American Life"), as do newer tunes and old standards alike. When the crowd loses its mind at the first strains of "Vogue," you'll be right there with them.